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排序方式: 共有1295条查询结果,搜索用时 15 毫秒
1.
Subcostal incision versus midline laparotomy in gallstone surgery: a prospective and randomized trial 总被引:1,自引:0,他引:1
J C García-Valdecasas R Almenara C Cabrer A M de Lacy M Sust P Taurá J Fuster L Grande M Pera J Sentis 《The British journal of surgery》1988,75(5):473-475
We report the results of a prospective and randomized trial designed to study the incidence of abdominal and pulmonary complications in gallstone surgery comparing subcostal (SI) with midline incision. The need for postoperative analgesia was lower in the SI group. There was no difference in the degree of hypoxaemia in the first two postoperative days, but there was less impairment of pulmonary function in terms of vital capacity and forced expiratory volume in 1 s (P less than 0.0001) in the SI group. SI patients also had a lower incidence of pulmonary or abdominal complications but the difference was not significant. Finally, we found a reduced hospital stay for the SI patients (P less than 0.01), probably related to a reduced postoperative analgesic requirement and an improved pulmonary function. We conclude that subcostal incision is a better approach for biliary tract surgery and should be used whenever possible. 相似文献
2.
M Daperno R Sostegni N Scaglione E Ercole C Rigazio R Rocca A Pera 《Digestive and liver disease》2004,36(1):21-28
BACKGROUND: Severe ulcerative colitis is potentially life threatening even though a policy of intensive medical management and early colectomy in recent years reduced mortality to almost zero. However, colectomy, with or without ileal-anal anastomosis, has its own problems (morbidity, pouchitis, cuffitis) and no reliable prognostic index of surgical outcome has been developed. Intravenous steroids are still the mainstay of medical therapy but their maximal duration before stating a 'treatment failure' has not been defined. AIM OF THE STUDY: To evaluate the effectiveness, safety and outcome of an intensive medical approach in a series of patients with severe ulcerative colitis. PATIENTS AND METHODS: One hundred and forty-nine episodes of severe ulcerative colitis in 115 patients admitted to a Gastroenterology Unit in a 7-year period were retrospectively evaluated. Intravenous glucocorticosteroids--methylprednisolone 1 mg/kg/day--and topical steroids were administered, and supportive treatments with intensive monitoring were extended to all the patients. Second-line strategies for steroid-refractoriness were prolonged glucocorticosteroids treatment, oral ciclosporin, infliximab or surgery. RESULTS: The median number of Truelove criteria at admission was 3 (range 2-5), median CRP 34 mg/l (range 10-196). Median follow-up after discharge was 49 months. In 84 (57%) episodes an early response was noted, while 65 (43%) did not respond within 10 days to the standard steroid treatment. In the non-responders group, 28 patients went into remission with a prolonged steroid treatment (slow responders); 15 patients were treated with ciclosporin (eight responders) and 6 with infliximab (four responders). A total of 24 colectomies was performed in this group of patients (in 21 cases within 30 days from admission). Slow responders showed lower albumin levels (P = 0.02), higher cumulative dose of glucocorticosteroids in the year prior to admission (P = 0.02) and higher age (P = 0.03), in comparison with early responders. Major complications were noted in four episodes which responded to medical treatment. Disease-related mortality was zero. CONCLUSIONS: Medical treatment and use of second-line therapies were effective in the present series of patients. A group of slow responders has been identified and, if an intensive medical monitoring is guaranteed, steroids can be safely prolonged after the first 10 days of treatment. Cumulatively, about 80% of the patients responded to short-term medical treatment, only 5% of the patients underwent colectomy in the follow-up period. Major adverse events were recorded in four patients, who had recovered completely after adequate medical treatment. 相似文献
3.
4.
The study aim was to evaluate the effect of different attentional tasks on the amplitudes and latencies of painful and non-painful contact heat evoked potentials (CHEPs). CHEPs were recorded in 12 healthy subjects during two experimental conditions, in which attention was oriented towards the intensity and the distress caused by the stimuli and were compared with CHEPs recorded during a neutral condition. The painful heat stimulation produced a negative potential at Cz vertex with a latency around 540 ms (Cz/N540), a positive peak at Cz electrode around 730 ms (Cz/P730) and, lastly, a positive peak around 1000 ms (Pz/P1000) in the Pz traces. The Cz/P730 wave was significantly higher in amplitude only during the painful stimulation and is probably related to coding the nociceptive activity. Varying the attentional target towards different properties of the stimulus did not cause any significant change in CHEP responses amplitude and latencies compared with the neutral condition. Our results suggest that CHEPs represent a reliable functional measure of the nociceptive pathways and that they are generated by the activation of different cerebral areas involved in pain processing. The high activation level of each of these area or their spatial neighbouring might explain the strong similarity of CHEP components recorded during different attentional manipulations. 相似文献
5.
6.
Massimiliano Valeriani Domenico Restuccia Vincenzo Di Lazzaro Domenica Le Pera Carmen Barba Pietro Tonali François Mauguiere 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(3):306-315
Brain electrical source analysis (BESA) of the scalp electroencephalographic activity is well adapted to distinguish neighbouring
cerebral generators precisely. Therefore, we performed dipolar source modelling in scalp medium nerve somatosensory evoked
potentials (SEPs) recorded at 1.5-Hz stimulation rate, where all the early components should be identifiable. We built a four-dipole
model, which was issued from the grand average, and applied it also to recordings from single individuals. Our model included
a dipole at the base of the skull and three other perirolandic dipoles. The first of the latter dipoles was tangentially oriented
and was active at the same latencies as the N20/P20 potential and, with opposite polarity, the P24/N24 response. The second
perirolandic dipole showed an initial peak of activity slightly earlier than that of the N20/P20 dipolar source and, later,
it was active at the same latency as the central P22 potential. Lastly, the third perirolandic dipole exaplaining the fronto-central
N30 potential scalp distribution was constantly more posterior than the first one. In order to evaluate the effect of an increasing
repetition frequency on the activity of SEP dipolar sources, we applied the model built from 1.5-Hz SEPs to traces recorded
at 3-Hz and 10-Hz repetition rates. We found that the 10-Hz stimulus frequency reduced selectively the later of the two activity
phases of the first perirolandic dipole. The decrement in strength of this dipolar source can be explained if we assume that:
(a) the later activity of the first perirolandic dipole can represent the inhibitory phase of a “primary response”; (b) two
different clusters of cells generate the opposite activities of the tangential perirolandic dipole. An additional finding
in our model was that two different perirolandic dipoles contribute to the centro-parietal N20 potential generation.
Received: 5 August 1997 / Accepted: 26 November 1997 相似文献
7.
Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
8.
High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes 总被引:5,自引:0,他引:5
Shuber AP; Michalowsky LA; Nass GS; Skoletsky J; Hire LM; Kotsopoulos SK; Phipps MF; Barberio DM; Klinger KW 《Human molecular genetics》1997,6(3):337-347
As more mutations are identified in genes of known sequence, there is a
crucial need in the areas of medical genetics and genome analysis for
rapid, accurate and cost-effective methods of mutation detection. We have
developed a multiplex allele-specific diagnostic assay (MASDA) for analysis
of large numbers of samples (> 500) simultaneously for a large number of
known mutations (> 100) in a single assay. MASDA utilizes
oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA
samples are immobilized on a solid support and a single hybridization is
performed with a pool of allele-specific oligonucleotide (ASO) probes. Any
probes complementary to specific mutations present in a given sample are in
effect affinity purified from the pool by the target DNA. Sequence-specific
band patterns (fingerprints), generated by chemical or enzymatic sequencing
of the bound ASO(s), easily identify the specific mutation(s). Using this
design, in a single diagnostic assay, we tested samples for 66 cystic
fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell
anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations,
four mutations in Canavan disease, four mutations in Fanconi anemia, and
five mutations in BRCA1. Each mutation was correctly identified. Finally,
in a blinded study of 106 of these mutations in > 500 patients, all
mutations were properly identified. There were no false positives or false
negatives. The MASDA assay is capable of detecting point mutations as well
as small insertion or deletion mutations. This technology is amenable to
automation and is suitable for immediate utilization for high-throughput
genetic diagnostics in clinical and research laboratories.
相似文献
9.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
相似文献
10.
M. Fiore C. Pera L. Delfino I. Scotese G. B. Ferrara C. Pignata 《International journal of immunogenetics》1995,22(5):403-411
IgA deficiency (IgA-D) represents the most common immunodeficiency syndrome of infancy. In most cases IgA-D represents an isolated immunological disorder, while sometimes it is associated with IgG subclass deficiency or with the presence of autoantibodies. We investigated the pattern of association of IgA-D with DRB1 and DQB1 loci of the HLA region by DNA molecular typing, which allows the identification of previously serologically undefined specificities. We also compared the gene frequency of DRB1 and DQB1 allelic variants between IgA-D subjects with or without serum autoantibodies. Our results indicate that the gene frequency of the DRB1*0102 subtype and of the DRBP0102, DQB1*0501 haplotype is significantly higher in IgA-D than in the general population. Furthermore, the IgA-D subjects with autoantibodies showed a positive association with DR4 and DR13 subtypes, thus supporting the hypothesis that genetic factors are also involved in the association between IgA-D and autoantibodies. 相似文献